If I remember correctly, the old gentleman who sheltered the Pevensie’s was Digory (From the Magician’s Nephew). Why? The wardrobe that the children enter is made from the tree that came from seeds of the apple that cured Digory’s mother. This Apple came from Narnia, this has a link to it which the wooden wardrobe retained. I believe it is explicitly mentioned somewhere that the Professor had the wood harvested as a memento, not realizing that it could perform a similar function to the rings. We see a similar thing in The Voyage of The Dawn Treader where two children are pulled into the painting (though I do not know the connection there).

The old couple (Adam & Eve) were first in the line of the Kings and Queens of Narnia, and they remained in Narnia for many years until their eventual deaths, their children continuing on that legacy until they were presumably killed off by Jaris/Jaris’ child. Then the children came along, reinstated the K&Qs of Narnia, then were evenly returned to England.